Kosovo will declare independence from Serbia "much earlier" than next May, the Kosovo Albanian government says.
Nato troops are stationed around Kosovo to protect Serbian enclaves
The statement came as a UN deadline for agreement on the future of the province expired. Months of talks had failed to break the deadlock.
EU nations failed to adopt a joint stance on whether to recognise independence at talks on Monday.
Serbia's president says he wants an international court to decide if the move to independence would be legal.
Boris Tadic said he wanted the UN Security Council to ask the International Court of Justice to examine the case.
Serbia has previously pledged to use all peaceful means to prevent Kosovo declaring independence - and it now seems the legal side of that campaign has begun, says the BBC's Nick Hawton in Belgrade.
Kosovo is still a province of Serbia but ethnic Albanian leaders there threatened to declare independence.
Kosovo government spokesman Skender Hyseni said a declaration of independence was not a matter of "if, but when".
"Kosovo will look at its own agenda, but it will certainly be much earlier than May," he said.
EU foreign ministers meeting in Brussels said they had come close to a common position, with the UK, Germany, France and Italy all indicating they would support a declaration of independence.
Only Cyprus still wants a UN Security Council resolution before accepting a declaration of independence.
There will be an EU summit at the end of the week at which leaders will be under pressure to issue a statement in favour of independence, our correspondent says.
On Monday, thousands of ethnic Albanian students marched from Pristina University to Kosovo's parliament demanding an immediate declaration of independence.
The marchers carried US and Albanian flags, as well as posters bearing slogans such as "Independence is the only option" and "Europe, show some unity."
Russia, a strong backer of Serbia, warned against a unilateral declaration of independence, saying it would "create a chain reaction throughout the Balkans and other areas of the world".
A march on Monday attracted thousands of Kosovo Albanians
UN Secretary General Ban Ki-moon had set a deadline of 10 December for mediators from the "troika" of the EU, US and Russia to broker a deal between Kosovo and Serbia, but the talks failed.
UN special envoy Martti Ahtisaari had put forward a plan offering Kosovo "supervised independence".
The plan - accepted by the ethnic Albanians - would have meant international agencies gradually steering Kosovo's institutions towards independence, while safeguarding the rights and property of the Serbian minority.
But Serbia rejected it, insisting that Kosovo must remain an integral part of Serbia.
Belgrade also fears discrimination against ethnic Serbs would go unpunished in an independent Kosovo.
Nato was criticised after it failed to prevent riots by ethnic Albanians in 2004 in which Serbs were attacked. Nineteen people died in the violence.
Nato - fearing a violent Serbian reaction - has said it will keep 16,000 troops in Kosovo to deter any clashes.
Though technically part of Serbia, Kosovo has been administered by the UN for the last eight years.
Belgrade's security forces were driven out of Kosovo by a Nato bombing campaign in 1999, launched to stop a violent Serbian crackdown on ethnic Albanians.